Which is the Divisor and Which is the Dividend?

Date: 03/01/2002 at 18:56:02
From: Ashley
Subject: Divisors, Dividends

Dear Dr. Math,

I like doing long division but I can't remember which number is the 
dividend and which is the divisor. 

Sincerely,
Ashley

Date: 03/01/2002 at 23:16:11
From: Doctor Peterson
Subject: Re: Divisors, Dividends

Hi, Ashley.

If you knew Latin you would have no trouble. The ending "-end" on 
dividend means "what something is going to be done to," so "dividend" 
means "the number being divided." The ending "-or," like "-er" in 
English, means "who is doing something," so "divisor" means "divider," 
"the number it is being divided BY." When you divide 63 by 9, 63 is 
being _divided_ (the dividend), and 9 is doing the dividing (the 
divisor).

When we write it this way, usually using the "bar-and-two-dots" 
division symbol (called an obelus)

    63 / 9 = 7

the number on the left is the dividend; it's being divided BY the 
second number. When we do the calculation like this

      ___7_
    9 ) 63

the number inside is the dividend. I once explained to a student that 
the 63 is lying on the operating table, and the 9 is the doctor 
standing next to the table operating on it. So the dividend is being 
divided by the divisor. (And the quotient is the organ he's just 
removed?) Maybe that picture can help.

- Doctor Peterson, The Math Forum
  http://mathforum.org/dr.math/